This invention relates to a photographic element having a support, at least one layer for carrying images on the support and also a protective coating layer, and a process for producing the same. More particularly, it pertains to a photographic element which can be prepared easily, and is excellent in adhesion to the layer forming the image and excellent in water resistance. The photographic element of the present invention can be utilized well particularly for, for example, identification card.
As the so-called ID card, such as employee certificate, credit card, driver license, passage admittance, there have been generally employed those having predetermined necessary informations, for example, particulars (informations) such as address, name, number on a support such as paper, plastic, etc. by printing, etc., and also identification informations such as photograph, etc. for identifying the person, applied with seal. However, this kind of identification card has the problem that falsifying such as forging, modification, etc. can be easily done. Also, these were weak in durability such as with friction, etc. and frequently suffered from contamination, breaking, etc. when carried at all times. As an improvement of such defect, recently used is made of a light-sensitive material having a light-sensitive emulsion such as silver halide emulsion coated on a support, and particulars are printed on said light-sensitive material and also a face picture of person is printed thereon. There have been also known those with various contrivances for prevention of falsifying, for example, one having the surface of a card coated with a resin film followed by hot seal, one having both surfaces of said card laminated with a resin film, etc. However, these can be also modified by peeling off the emulsion surface and the resin film of the light-sensitive material, thus proving to be no complete prevention of falsifying, and besides there has been the fear of discoloration, thus posing a problem in durability. Further, those adhered or laminated onto a resin film suffered from problems that complicated devices such as hot melting device, lamination device and complicated steps are required, whereby no inexpensive ID card can be obtained.
As the method for solving these, there has been known the technique in which an active energy curable composition is applied on the image forming layer, and then said composition is cured with an active energy ray to form a protective coating layer.
As the method for obtaining a protective layer by curing with an active energy ray, there have been known the techniques for providing UV-ray curable protective coating layers for the purpose of imparting scratching resistance, abrasion resistance, blooming resistance, etc. to the photographic material after formation of image. For example, in Japanese Unexamined Patent Publication No. 57023/1978, U.S. Pat. Nos. 4,171,979, 4,049,861 and 4,333,998, Japanese Unexamined Patent Publications Nos. 121100/1978 and 91233/1981 and Japanese Unexamined PCT Patent Publication No. 501642/1984, there are disclosed the method in which a composition containing an acrylic prepolymer having unsaturated groups and a polymerization initiator generating photoradicals is coated to effect curing by way of radical polymerization, and the technique in which curing is effected by using in combination an epoxy resin, an acrylic prepolymer, a cation polymerization initiator and a radical polymerization initiator. However, these protective layers, although having sufficient performances in improvement of abrasion of films for projection and in handling of print films, are entirely unsatisfactory when this technique is applied to ID card, and the characteristics demanded in ID card, particularly water resistance and adhesion, cannot be obtained sufficiently.
More specifically, when an active energy ray curable resin is to be used as the protective layer on a silver halide photographic emulsion, the problem will generally occur in acrylic polymers in adhesion to the emulsion layer, requiring sometimes an intermediate layer. As the technique for improving the adhesion, there have been disclosed methods in which acrylate oligomers, and compounds having reactivity with or affinity for gelatin are used in combination in Japanese Unexamined Patent Publications Nos. 201248/1986, 201250/1986, 201249/1986, 201251/1986, but although there may be the effect of improvement of adhesion, it is still insufficient, and also light resistance is not sufficient, thus being not necessarily satisfactory in photographic performances. On the other hand, in the case of the epoxy type polymer, it has been found that the problem may sometimes occur with respect to its curability on account of sodium sulfite.
Examples of using curable coating layers coated with compositions containing epoxy resins and cation polymerization initiators for ID card are disclosed in Japanese Unexamined Patent Publications Nos. 90789/1982, 21150/1987, 23042/1987, 23043/1987, 24256/1987, 25758/1987 and 29133/1987. However, under various conditions where ID card is used, it is impossible to satisfy all of necessary adhesion, water resistance, pinhole characteristic, contamination resistance when damaged, and a very great curing device is required for satisfying all of these according to the techniques listed above and it is difficult to prepare simply an inexpensive card.
Also, as the technique for improving adhesion by use of an acrylate oligomer and an epoxy type polymer, Japanese Unexamined Patent Publications No. 229133/1987 discloses the technique of using a specific film hardener in the layer adjacent to the UV-ray curable layer, and its effect is greater as the amount of the film hardener used is larger, but there is the problem that the photographic sensitivity will be lowered in that case.